What is the meaning of Short_sale?

A property sale negotiated with a mortgage company in which a lender takes less than the total amount due.

A sale of a third-party bond, share, or similar financial instrument that entails borrowing the asset together with a concurrent obligation to transfer its ownership to a subsequent buyer (or to the original seller) in the hope that the price will decrease before any loan must be repaid or relevant fees become due.

A sale of a financial security, commodity, or other third-party asset that entails a contractual obligation to deliver the asset to a subsequent buyer at a specified date.

Source: wiktionary.org